The following gives some background to drainage legislation, and related drainage regulations and rules.

In January 2015, DEFRA released the Small Sewage Discharge General Binding Rules regulating septic tanks and small sewage treatment plants in England.

Introduced to simplify the regulation process, as well as protecting the environment and improving water quality.

If you have a septic tank or small sewage treatment plant then you must follow the ‘general binding rules’ by maintaining your system so it does not cause pollution.

The drainage regulations are quite simple, see the General Binding Rules Guide on the Environment Agency website here or get in touch with us. Croft Drainage cover drainage solutions in Lincolnshire, Nottinghamshire and Yorkshire.

Historically some septic tanks discharged directly to surface water. Now under the general binding rules discharges from septic tanks directly to surface water are not allowed.

If you have a septic tank that discharges directly to surface water you will need to replace or upgrade your treatment system by the 1st of January 2020. Or when you sell your property if it is before this date. We also provide pre-sale surveys in Lincolnshire if you are thinking of moving house and want to check the drainage supply.

If the Environment Agency finds evidence that you are not complying with drainage regulations and your septic tank discharging to a surface water is causing pollution, you will need to replace or upgrade your system earlier than the 1st of January 2020. You will usually have to do this within 1 year, agreed on a case-by-case basis.

What are your options?

Croft Drainage Solutions can survey your property.

During our surveys we identify any issues and guide you through changes needed to allow you to comply with the drainage regulations.

You may be able to:


  • Connect to a main sewer if one is available. Normally you need to be greater than 30 metres from a main sewer for a single dwelling to install a septic tank
  • Install a drainage field so the septic tank can discharge to ground instead
  • Replace your septic tank with a small sewage treatment plant

Do I need a discharge permit?

You probably won’t need a discharge premit, but you must abide by the Environment Agency General Binding Rules.

If you don’t follow these General Binding rules, then you will need a Permit for the discharge.

In simple terms the requirements depend on the volume of the discharge and the nature of the effluent.
In summary:

  • To make a discharge of more than 5 m3/day (5,000 litres) of treated sewage effluent or wastewater to surface water (for example a river, stream, pond, lake, estuary or the sea), or to groundwater (including via an infiltration trench or soakaway system) then you will have to apply for an Environmental Permit to make that discharge
  • If you want to discharge treated sewage effluent, to a river, stream, estuary or the sea and the volume is 5 m3/day or less (5,000 litres) you might be eligible for an exemption rather than a permit
  • Discharging sewage effluent, to groundwater via a drainage field or infiltration system and the volume is 2 cubic metres per day or less (2,000 litres) you might be eligible for an exemption rather than a permit.

Do I require planning permission for a new septic tank or sewage treatment plant or for repairing an existing one?

Meeting the requirements of the Building Regulations is the responsibility of the person carrying out the building work and, if they are not the same person, the owner of the building. Approval is important as the building regulations apply to most building work. Building Regulations Approved Document H (Drainage & Waste Disposal) covers Cesspits, Septic Tanks, Sewage Treatment Plants and Drainage Fields.

Will I need planning permission?

Check with your local planning department but usually a new septic tank will require planning permission. If you are replacing an existing system with an upgraded one, then it is likely that you don’t. All that you will require is Building Regulations approval.  If it is a completely new system, then the likelihood is that you will need planning permission.

Plans for new septic tanks in new properties or developments should be within the main planning approval for the new build project. Installation of the new septic tank will have to be in accordance with Building Regulations.

Will I need Building Regulations approval?

Yes, all work will require signing off by the building regulations department of your local council.

Building Regulations (section H2) cover the installation of septic tanks and other off mains drainage systems. Click here for link to full document.

The owner is legally responsible for ensuring that the system doesn’t ‘cause pollution, a health hazard or a nuisance’. Local Authorities have the powers to test any off-mains system that they think are causing a problem. They can take action if they find any issues.

Environment Agency PPG4 (Pollution Prevention Guidelines)

The PPG4 helps you to work out which type of drainage system is suitable for your property. It also tells you when you need to gain consent from the EA.

The document contains information about percolation tests and drainage field size. Percolation tests assess the porosity of the soil at your property. Which is a good guide to the suitability of your land for a drainage field. Take a look at the full document here.

Contact Croft Drainage Solutions if you require help with your percolation tests.

Flows and Loads

This details the size that any septic tank, sewage treatment plant or cesspit needs to be to serve the property (or properties) connected to it.

Tanks come in different sizes to suit the site conditions. The number of bedrooms a domestic property has will govern the size of the tank.

The link to the full document is here.

At Croft Drainage Solutions we have experience of working with these regulations and guidelines. If you need any assistance contact us.